1. Field of the Invention
The present invention relates to a device for a motor vehicle that affords occupant protection during the impact of energy directed against a motor vehicle door.
2. Description of the Prior Art
Occupant protection in motor vehicles is a major concern in the construction and development of new motor vehicles. A development goal is designing a distinct crumble zone in the front and rear part of the vehicle capable of protecting the occupant compartment in collisions from the front and the rear. Occupant protection, however, presents greater problems in collisions from the side due to the short deformation path and the minimal absorption capacity of the lateral structure of the vehicle. Prior art solutions to mitigate occupant risk in lateral collisions provide for reinforcement of the vehicle door. For example, molding integrated in the vehicle door is known which possesses great rigidity in the transverse direction of the vehicle and/or possesses great capacity to absorb energy. For example, DE 196 33 637 A1 describes a vehicle door with lateral impact protection in which the door frames are provided with arch-shaped stay bars which are twisted during collision and deformed under tensile load in such a manner that the effect is similar to that of a guard net.
However, such reinforcement of the side doors by providing corresponding longitudinal beams is not always sufficient enough to protect the occupants in bad collisions as the side door can be pressed through the door opening of the vehicle body upon impact of external forces so that the occupant survival space is drastically reduced and consequently chances of survival.
Furthermore, in the state of the art, a series of measures are known that are suited to transfer forces acting on the side door to the body of the motor vehicle, for example by corresponding large-scale overlapping between the door and the door opening or by bolts extending from the edge of the door. In the case of a collision the bolts mesh in reinforced recesses in the door opening of the motor vehicle body. DE AS 22 15 674 describes a means of reinforcing a motor vehicle door essentially comprising an outward-curving beam whose end sections enter corresponding stable recesses when the beam is deformed as the result of an external impact. The beam preferably comprises molded steel sheet formed into the respective shape.
To prevent the preceding measures from increasing the weight of the motor vehicle, DE 41 25 299 C2 describes a means of reinforcing a motor vehicle door, comprising an arch-shaped reinforcement means made of fiber-reinforced composite material for weight reduction. In this case, too, the reinforcement device is located completely inside the door. The reinforcement device comes out of the door with its end sections only in a collision as a result of the deformation of the reinforcement beam. The end sections, in turn, then enter an active connection with the stable support flanks in the door frame of the motor vehicle body.
DE 198 39 519 A1 describes a passenger compartment that provides a transverse beam construction as a means of occupant protection in a lateral collision. In a collision, the transverse beam construction creates a rigid transverse connection between the vehicle door and the center console in such a manner that the seat area in front of the area where the vehicle door enters the passenger compartment should be protected. The transverse beam construction only appears if there is a collision in that pyrotechnical or pneumatic actors extend a hinged cross beam construction, which is otherwise integrated in the seat, door and covering of the console covering, forming a stable transverse connection.